import React, {useState} from 'react';

import {postJson} from '../api';
import {daysBefore, localToday} from '../dates';
import {errorMessages} from '../errors';
import CropDetails from './CropDetails';
import CropPicker from './CropPicker';
import Modal from './Modal';
import SeedPacket from './SeedPacket';
import SeedPacketList from './SeedPacketList';
import Steps from './Steps';
import WhenPicker from './WhenPicker';

const STEPS = ['Which seeds', 'Where and when', 'Notes'];
const SOURCES = [['mine', 'From my seeds'], ['new', 'New seeds'], ['seedlings', 'Seedlings I got']];

// A row of radio pills, the same look as the "when" choice.
function Choices({id, legend, choices, value, onChange}) {
  return (
    <fieldset className="mt-4">
      <legend className="crop-picker-label step-legend">{legend}</legend>
      <div className="pill-choices">
        {choices.map(([choice, label]) => (
          <React.Fragment key={choice}>
            <input
              type="radio"
              className="visually-hidden"
              name={id}
              id={`${id}-${choice}`}
              checked={value === choice}
              onChange={() => onChange(choice)}
            />
            <label className="pill-choice" htmlFor={`${id}-${choice}`}>{label}</label>
          </React.Fragment>
        ))}
      </div>
    </fieldset>
  );
}

// "Sow seeds", in steps: which seeds (a packet of your own, new seeds, or
// seedlings you were given), then where and when, then any notes. Choosing the
// seeds goes straight on to the next step. Sowing from a packet takes the seeds
// out of it.
export default function SowSeedsModal({nursery, gardens, seeds, onClose, onSown}) {
  const [step, setStep] = useState(1);
  const [source, setSource] = useState(seeds.length > 0 ? 'mine' : 'new');
  const [search, setSearch] = useState('');
  const [seed, setSeed] = useState(null);
  const [crop, setCrop] = useState(null);
  const [when, setWhen] = useState('today');
  const [customDate, setCustomDate] = useState('');
  const [where, setWhere] = useState('nursery');
  const [gardenId, setGardenId] = useState(gardens.length > 0 ? String(gardens[0].id) : '');
  const [quantity, setQuantity] = useState(6);
  const [note, setNote] = useState('');
  const [saving, setSaving] = useState(false);
  const [errors, setErrors] = useState([]);
  const [sown, setSown] = useState(null);
  const [placing, setPlacing] = useState(null); // sown straight into a garden: offer to place it on the layout

  const today = localToday();
  const sownOn = {today, yesterday: daysBefore(today, 1), other: customDate}[when];
  const garden = where === 'nursery' ? nursery : gardens.find((g) => String(g.id) === gardenId);
  const cropId = source === 'mine' ? seed && seed.crop_id : crop && crop.id;
  const cropName = source === 'mine' ? seed && seed.name : crop && crop.name;
  const target = where === 'nursery' ? 'the nursery' : (garden ? garden.name : 'a garden');
  const quantityLabel = source === 'seedlings' ? 'How many seedlings?' : 'How many seeds?';
  const detailsReady = Boolean(garden) && quantity > 0 && Boolean(sownOn) && sownOn <= today;

  function chooseSource(choice) {
    setSource(choice);
    setSeed(null);
    setCrop(null);
  }

  function chooseSeed(packet) {
    setSeed(packet);
    setStep(2);
  }

  function chooseCrop(chosen) {
    setCrop(chosen);
    setStep(2);
  }

  // Back to choosing the seeds, for the next sowing.
  function startAgain() {
    setSeed(null);
    setCrop(null);
    setNote('');
    setStep(1);
  }

  async function save(addAnother) {
    setSaving(true);
    setErrors([]);
    try {
      const planting = {
        garden_id: garden.id,
        crop_id: cropId,
        quantity,
        planted_from: source === 'seedlings' ? 'seedling' : 'seed',
        ...(source === 'mine' ? {parent_seed_id: seed.id} : {}),
        planted_at: sownOn,
        ...(note.trim() ? {description: note.trim()} : {}),
      };
      const {ok, status, data} = await postJson('/plantings.json', {planting, ...(source === 'mine' ? {use_seeds: 1} : {})});
      if (!ok) {
        setErrors(errorMessages(status, data, {forbidden: 'You can\'t sow into that garden.', signedOut: 'Please sign in again to sow seeds.'}));
      } else if (addAnother) {
        setSown(`Sowed ${quantity} ${cropName}.`);
        startAgain();
      } else if (where === 'garden') {
        setPlacing({quantity, name: cropName, garden, saved: data});
      } else {
        await onSown(data); // keeps saying so until the page shows it
        return;
      }
    } catch (error) {
      setErrors(['Couldn\'t reach the server. Please try again.']);
    }
    setSaving(false);
  }

  // What was chosen, as a packet or a crop, with a way back to change it.
  const chosen = () => (
    <>
      <button type="button" className="btn btn-sm btn-outline-secondary mb-2" onClick={() => setStep(1)}>Change seeds</button>
      {source === 'mine' ? <SeedPacket packet={seed} /> : <CropDetails slug={crop.slug} />}
    </>
  );

  if (placing) {
    return (
      <Modal title="Sow seeds" titleId="sow-seeds-title" onClose={() => onSown(placing.saved)}>
        <div className="modal-body plant-dialog-body">
          <div className="alert alert-success" role="status">
            <strong>Sowed {placing.quantity} {placing.name} into {placing.garden.name}.</strong>
          </div>
          <h3 className="h5">Where in the garden did you put them?</h3>
          <p>Add it to the garden layout to remember where it is. You can do this later from the garden.</p>
          <a className="btn btn-success" href={`/gardens/${placing.garden.slug}/layout`}>Place on the garden layout</a>{' '}
          <button type="button" className="btn btn-outline-success" onClick={() => onSown(placing.saved)}>Not now</button>
        </div>
      </Modal>
    );
  }

  return (
    <Modal title="Sow seeds" titleId="sow-seeds-title" size="xl" onClose={onClose}>
      <div className="modal-body plant-dialog-body sow-seeds">
        <Steps steps={STEPS} current={step} />
        {errors.length > 0 && (
          <div className="alert alert-danger" role="alert">
            <strong>That didn&rsquo;t work.</strong>
            <ul className="mb-0">{errors.map((message) => <li key={message}>{message}</li>)}</ul>
          </div>
        )}
        {sown && <div className="alert alert-success" role="status">{sown} Sow another below.</div>}

        {step === 1 && (
          <>
            <Choices id="sow-source" legend="Where do the seeds come from?" choices={SOURCES} value={source} onChange={chooseSource} />
            <div className="mt-3">
              {source === 'mine' ? (
                <SeedPacketList packets={seeds} search={search} onSearch={setSearch} selected={seed} onChoose={chooseSeed} sownOn={sownOn} />
              ) : (
                <CropPicker id="sow-crop" label="Which crop?" onChoose={chooseCrop} />
              )}
            </div>
          </>
        )}

        {step === 2 && (
          <div className="sow-grid">
            <div className="sow-settings">
              <WhenPicker
                id="sow-seeds"
                legend="When"
                max={today}
                when={when}
                onWhen={(choice) => { setWhen(choice); if (choice === 'other' && !customDate) setCustomDate(today); }}
                date={customDate}
                onDate={(event) => setCustomDate(event.target.value)}
                hint={sownOn > today ? 'Seeds can only be sown up to today.' : sownOn}
              />
              <Choices
                id="sow-where"
                legend="Where are you sowing them?"
                choices={[['nursery', 'Into the nursery'], ['garden', 'Straight into a garden']]}
                value={where}
                onChange={setWhere}
              />
              <p className="form-text">
                {where === 'nursery'
                  ? 'They stay in the nursery as seedlings until you transplant them.'
                  : 'They go in as a planting, with no nursery stage.'}
              </p>
              {where === 'garden' && (
                gardens.length > 0 ? (
                  <>
                    <label className="form-label" htmlFor="sow-garden">Which garden?</label>
                    <select id="sow-garden" className="form-select" value={gardenId} onChange={(event) => setGardenId(event.target.value)}>
                      {gardens.map((g) => <option key={g.id} value={g.id}>{g.name}</option>)}
                    </select>
                  </>
                ) : <p className="text-muted">You don&rsquo;t have another garden yet.</p>
              )}
              <label className="form-label mt-4" htmlFor="sow-quantity">{quantityLabel}</label>
              <input
                id="sow-quantity"
                className="form-control sow-quantity"
                type="number"
                min="1"
                value={quantity}
                onChange={(event) => setQuantity(Math.max(0, parseInt(event.target.value, 10) || 0))}
              />
              {source === 'mine' && seed.quantity != null && (
                <p className="form-text">That packet goes from {seed.quantity} to {Math.max(0, seed.quantity - quantity)}.</p>
              )}
            </div>
            <div className="sow-chooser">{chosen()}</div>
          </div>
        )}

        {step === 3 && (
          <>
            <p className="lead">Sowing {quantity} {cropName} into {target}{sownOn === today ? ' today' : ` on ${sownOn}`}.</p>
            <label className="form-label" htmlFor="sow-note">Do you have any notes for this planting? (optional)</label>
            <textarea id="sow-note" className="form-control" rows="4" value={note} onChange={(event) => setNote(event.target.value)} />
          </>
        )}
      </div>
      <div className="modal-footer">
        <button type="button" className="btn btn-link" onClick={onClose} disabled={saving}>Cancel</button>
        {step > 1 && (
          <button type="button" className="btn btn-outline-secondary" onClick={() => setStep(step - 1)} disabled={saving}>Back</button>
        )}
        {step === 1 && Boolean(cropId) && (
          <button type="button" className="btn btn-success" onClick={() => setStep(2)}>Next</button>
        )}
        {step === 2 && (
          <button type="button" className="btn btn-success" onClick={() => setStep(3)} disabled={!detailsReady}>Next</button>
        )}
        {step === 3 && (
          <>
            <button type="button" className="btn btn-outline-success" onClick={() => save(true)} disabled={saving}>Sow and add another</button>
            <button type="button" className="btn btn-success" onClick={() => save(false)} disabled={saving} aria-busy={saving}>
              {saving ? <><i className="fas fa-spinner fa-spin" aria-hidden="true" /> Sowing…</> : `Sow into ${target}`}
            </button>
          </>
        )}
      </div>
    </Modal>
  );
}